To provide a vitrified bond grindstone capable of suppressing infiltration of vitrified bond into porous ceramic holes by filling a substance which is more fragile than porous ceramic and does not disappear even at firing temperature of the vitrified bond, into the porous ceramic holes, and promoting fracturing of the porous ceramic in grinding.

A super abrasive grain 12 consisting of cubic crystal boron nitride grains or diamond grains and aggregate 14 are contained in vitrified bond 16, the aggregate consists of: porous ceramic 14a; and a substance 14b blocking porous ceramics holes. The substance has a physical property which is more fragile than the porous ceramic and does not disappear at a firing temperature of the vitrified bond.